Clip crimping tools are utilized in industries in which it is necessary to have a fast, efficient and effective method of quickly applying and crimping clips on to various objects. In one particular application, clip crimping tools are used to connect two wires in furniture springs, for example, within a mattress or chair assembly. Generally speaking, the clip crimping tool is placed around two wires to be secured and is then operated such that a clip is fed around the wires and is then crimped to secure the wires together.
In the past, clip crimping tools have been available. However, they were large and bulky, using complicated mechanisms to provide the necessary crimping force. In particular, in some pneumatic clip crimping tools, the pneumatic valve system had a large and complex design, involving a main valve that was provided adjacent to the air inlet or that was provided in a separate area from the piston cylinder.
In U.S. Pat. No. 3,641,656, there is described a clip crimping tool that includes a pneumatic system for providing the driving force. In this clip crimping tool, the pneumatic system was arranged such that the pneumatic driving force was directed perpendicularly to the required direction of the crimping force. This was necessary because the pneumatic system was large and complex. A linking mechanism was provided to transfer the pneumatic driving force to the direction of the crimping force.
This arrangement had several disadvantages. For example, the use of a large and complex pneumatic system, including the mechanism for transferring the force, required additional materials and was more costly in terms of construction and maintenance. The larger size of the pneumatic system also resulted in more difficult manipulation of and operation of the clip crimping tool.
Further, since the pneumatic system was disposed perpendicular to the direction of the required force, the efficiency of the force transfer was compromised. The requirement of providing a linking mechanism reduced the efficiency of the force transfer and also added extra weight to the clip crimping tool. This weight factor is particularly important in hand-held units.
This prior design of the pneumatic mechanism also had a disadvantage in that the main valve was provided adjacent to the air intake and was only connected to the piston cylinder through a small access tube. The small size of the air intake, main valve, and access tube impeded the free-flow of air and resulted in a slow action of the piston cylinder and thus a slower action of the clip crimping tool.
Clearly there is a need for an improved clip crimping tool that provides a less restricted flow of air, provides a smooth and direct action, and reduces stress on the operator.